The present invention relates to a damping arrangement effective during the transfer of intermittent movements of counter wheels in counters, particularly for the tens-transfer in rapidly rotating counters.
In gas stations, where gasoline is automatically metered, counters including a plurality of ordinal counter wheels are used, which are connected with each other by tens-transfer means.
It is necessary that the counter wheels have large indicating wheels which require that the counter wheels have certain minimum size, and consequently a certain minimum mass which cannot be further reduced without impairing the legibility of the indication. Particularly, with the counter wheel of the lowest order, which is the driven input counter wheel and indicates the smallest units, difficulties occur because a minimum size and mass cannot be further reduced, while on the other hand, for economic reasons, the greatest possible amount of flow of liquid through apparatus is to be registered. Particularly the number wheels of the lowest order, and during the tens-transfer also the number wheels of the higher orders, must be driven at very high rotary speeds, and must be able to withstand the high loads resulting therefrom.
In known counters, the input counter roller is continuously rotated by means of a gear secured to the respective counter wheel. During a transfer operation by which a unit has to be transferred to the next higher order and if necessary also to further higher orders, a transfer lug, which is fixedly connected with the input counter wheel, strikes while rotating at high speed, the toothed flanks of a tens-transfer gear which turns about an axis parallel to the axis of the counter wheels. The tens-transfer gear also meshes with the gear of the counter wheel of the next higher order and cooperates with a cam disc which locks the transfer gear, but releases the transfer gear for angular movement when a unit is to be transferred.
Counters of this type have the great disadvantage that the transfer lug strikes the respective tooth of the transfer gear, which is at first at a standstill, with a very hard impact. In the same moment, acceleration of a mass is required, which depends on the number of counter wheels to be shifted, and the accelerated masses must be rapidly decelerated until the transfer gear is again in the normal position. The occurring force peaks must be sustained without damping, and even if high quality material is used, disturbances and damage frequently occur, because the material cannot resist the high stresses. Furthermore, the load peaks of the impacts have also an effect on the drive means of the counter, and may detrimentally influence the precision of the values metered by the counter, and the exact transfer of such values to the indicator.
Another construction of the prior art provides a transfer means which consists of two coupling elements connected by a torsion spring. To assure the complete transfer operation, additional connecting means are required, and the device consists of a great number of parts so that manufacture and maintenance is expensive. The resilient coupling element has no effect during a rapid deceleration after completion of the tens-transfer.